<template>
  <section class="msite">
    <!--首页头部-->
    <HeaderTop :title="address.name">
    
      <router-link class="header_search" slot="left" to="/search">
        <i class="iconfont icon-sousuo"></i>
      </router-link>
      <router-link class="header_login" slot="right" :to="userInfo._id ? '/main': '/login'">
        <span class="header_login_text" v-if="!userInfo._id">登录|注册</span>
        <i class="iconfont icon-person" v-else></i>
      </router-link>
    </HeaderTop>
    <!--首页导航-->
    <nav class="msite_nav">
      <div class="swiper" v-if="categorys.length">
        <div class="swiper-wrapper" >
          <!-- 根据categoryArr中的数据循环生成categorys数组 （两个空数组）-->
          <div class="swiper-slide" v-for="(categorys,index) in categoryArr" :key="index">
            <!-- 根据categorys数组中每个数据的参数生成category数组 （一个数组中的8个数据）-->
            <a href="javascript:" class="link_to_food" v-for="(category,index) in categorys" :key="index">
              <div class="food_container">
                <img :src="ImgUrl+category.image_url" />
              </div>
              <span>{{category.title}}</span> 
            </a>
          </div>
        </div>
        <!-- Add Pagination -->
        <div class="swiper-pagination"></div>
      </div>
      <img src="./images/msite_back.svg" alt="back" v-else>
    </nav>
    <!--首页附近商家-->
    <div class="msite_shop_list">
      <div class="shop_header">
        <i class="iconfont icon-xuanxiang"></i>
        <span class="shop_header_title">附近商家</span>
      </div>
      <ShopList></ShopList>
    </div>
  </section>
</template>

<script>
import HeaderTop from "../../components/HeaderTop/HeaderTop.vue";
import ShopList from "@/components/ShopList/ShopList.vue";
import { mapState } from "vuex";
//修改了下面这行代码
import Swiper, {Navigation, Pagination} from "swiper";
import "swiper/swiper-bundle.min.css";
//新加了下面这行代码
Swiper.use([Navigation, Pagination]);

export default {
  data(){
    return{
      ImgUrl:'https://fuss10.elemecdn.com'
    }
    
  },
  mounted() {
    this.$store.dispatch("getFoodCategorys"),
    // this.$store.dispatch("getAddress");
    this.$store.dispatch("getshops");
    
  },
  watch:{
    categorys(){ //监视数据更新
    // 要写在数据更新之后
      this.$nextTick(()=>{ //当数据更新时立即调用（swiper函数）等待界面更新
        new Swiper(".swiper", {
        loop: true, // 循环模式选项
      // 如果需要分页器
        pagination: {
          el: ".swiper-pagination",
        },
    });
      })
    }
   
  },
  computed: {
    // 使用mapState,调用state中的数据
    ...mapState(["address", "categorys",'userInfo']),
    // 创建一个函数，将state中categorys的转换成数组
    categoryArr(){
      // 使用解构赋值指向state中categorys
      const { categorys } = this;
      // 创建一个空数组（大数组）
      const Arr = [];
      // 创建一个空数组（小数组）
      let minArr = [];
      // 将categorys中的数据进行遍历循环（x）代表每一个数据
      categorys.forEach((x) => {
        // 先创建小数组放到大数组中（关联上）在把数据放到小数组中
        // 当小数组的长度=8的时候将重新创建一个空数组
        if (minArr.length === 8) {
          minArr = [];
        }
        // 当小数组长度=0的时候将小数组放到大数组中
        if (minArr.length === 0) {
          Arr.push(minArr);
        }
        // 将遍历循环的数据放进小数组中
        minArr.push(x);
      });
      return Arr  //把数组返回给categoryArr函数
    },
  },
  name: "MainFile",
  components: {
    HeaderTop,
    ShopList,
  },
};
</script>

<style lang='stylus' ref='stylesheet/stylus'>
@import '../../common/stylus/mixins.styl';

.msite { // 首页
  width: 100%;

  .msite_nav {
    bottom-border-1px(#e4e4e4);
    margin-top: 45px;
    height: 200px;
    background: #fff;

    .swiper {
      width: 100%;
      height: 100%;

      .swiper-wrapper {
        width: 100%;
        height: 100%;

        .swiper-slide {
          display: flex;
          justify-content: center;
          align-items: flex-start;
          flex-wrap: wrap;

          .link_to_food {
            width: 25%;

            .food_container {
              display: block;
              width: 100%;
              text-align: center;
              padding-bottom: 10px;
              font-size: 0;

              img {
                display: inline-block;
                width: 50px;
                height: 50px;
              }
            }

            span {
              display: block;
              width: 100%;
              text-align: center;
              font-size: 13px;
              color: #666;
            }
          }
        }
      }

      .swiper-pagination {
        >span.swiper-pagination-bullet-active {
          background: #02a774;
        }
      }
    }
  }

  .msite_shop_list {
    top-border-1px(#e4e4e4);
    margin-top: 10px;
    background: #fff;

    .shop_header {
      padding: 10px 10px 0;

      .shop_icon {
        margin-left: 5px;
        color: #999;
      }

      .shop_header_title {
        color: #999;
        font-size: 14px;
        line-height: 20px;
      }
    }
  }
}
</style>